Use a spring.
If you want to use a motor, then I would not bother with the current feedback. The RPM is close enough to zero that the motor will have a pretty constant relationship from input PWM to output torque.
Use a spring.
If you want to use a motor, then I would not bother with the current feedback. The RPM is close enough to zero that the motor will have a pretty constant relationship from input PWM to output torque.